1. Field of the Invention
This invention relates to simplified automated collection of environmental data, and particularly to the collection of rainfall, water flow rates in open channels and water level data in shallow groundwater, streams, open channels and wetlands by a modular data acquisition system.
2. Discussion of the Problem Solved
Environmental data is often collected to determine the functioning and characteristics of a site. Hydrologic data, including rainfall, open channel flow, groundwater levels, stream stage and wetland stage are commonly collected parameters. Increased concern with the health of the environment has prompted the collection of these data for several types of studies and disciplines.
There is a growing trend to use site specific data to evaluate the impact of various actions, such as land development or other human intervention, on the natural environment. A variety of professionals with different technical skills including biologists, ecologists, public health regulators, septic system designers, land developers, land planners, hydrologists, engineers and geologists have a need for site specific data to make better land use decisions. Typical applications in which site specific environmental data are needed include onsite septic site monitoring, wetland monitoring and stream gaging programs.
Improper siting, a common cause of septic system failure, can be avoided with more intensive collection of groundwater level and rainfall data. Successful functioning of a septic system requires vertical separation of the septic leaching zone from the water table. To ascertain whether this critical vertical separation of the septic leaching zone and water table will be maintained during wet periods of weather, it would be useful to continuously monitor rainfall and groundwater level simultaneously for extended periods to better evaluate a site's suitability for onsite sewage treatment, thereby increasing a system's probability for success.
Cumulative loss of wetlands is a problem of national concern. Whether or not a particular piece of land meets the jurisdictional definition of a wetland typically involves an evaluation of the site's soil, vegetation and hydrology. Depending upon the jurisdiction, the definition may vary. All definitions currently in use, however, evaluate the water table level during the growing season to determine if a site meets the hydrologic requirements of the wetland definition. The hydrologic characteristics of wetlands, particularly fluctuations in water level as a function of rainfall, are often used as a parameter to evaluate the hydrologic function of wetlands. Wetland monitoring programs are often designed to evaluate impacts of land development on wetland hydrology or to determine the success of a wetland mitigation. Similar data are also used in evaluating the hydrology of a site to design constructed wetlands or improve existing disturbed wetlands. Decision makers could benefit if site specific rainfall and wetland water level data were readily available. The data could be used to make more accurate wetland delineations and determinations. The data would also increase the success of constructed wetlands and wetland mitigations.
A national trend has developed in recent years in monitoring stream levels and flow rates to evaluate flooding potential, to monitor habitat quality and to provide baseline information for tracking the health of stream ecosystems. Stream gaging programs are often sponsored by public and nonprofit organizations, often employing the labor of volunteers who usually are not technically oriented.
Collection of simple environmental data can be complicated. Data collection involves several steps, including selection of monitoring equipment, assembly of instrumentation, programming, field installation, maintenance, data recording, data downloading and disassembly of field installation upon project completion. In selecting monitoring equipment, various components may not all be available from the same vendor and may not be compatible, further complicating the procurement and installation of equipment. Installing the system often requires some level of understanding of electronics and wiring of components is usually involved.
Prior art data acquisition systems are often designed to be multi-functional. Data recorders for instance, are often designed to accept a variety of different sensors. This feature of prior art systems can make them difficult to use. Many potential users are deferred by the prospect of having to climb a steep learning curve in the start-up phase of using prior art data acquisition systems.
Acquiring simple environmental data as described above with prior art systems typically requires a level of knowledge of controller programming and electronics. Many potential beneficiaries of data would be more inclined to collect data if the process were simpler than with prior art systems. The availability of simpler methods to collect data would most likely result in more data being collected to enable better decisions in assessing and protecting our nation's natural resources. A data acquisition system is needed which is a complete compatible package, quick and easy to install in the field, compact, simple to use and which has built in protection from theft and vandalism.